A User-Driven Selection of Vgi Based on Minimum Acceptable Quality Levels

Abstract

ABSTRACT:Despite Volunteered Geographic Information (VGI) activities are now extremely helpful in a number of scientific applications, researchers and decision makers oppose some resistance to the usage of volunteered contributions, due to quality issues. Several methods and workflows have been proposed to face quality issues in different VGI projects, usually built ad-hoc for specific datasets, thus resulting neither extensible nor transferable. In order to overcome this weakness, the authors propose to perform an user-driven assessment on VGI items in order to filter only those that satisfy minimally acceptable quality levels defined according to their specific quality requirements and project goals. In the present work the users, i.e., information consumers, are seen as decision makers and are allowed to set the minimum acceptable quality levels Thus the approach proposes a user driven assessment of the fitness for use of VGI items. The paper first briefly presents a view on VGI components and suitable quality indices, then it describes a logic architecture for managing them and for enabling a querying mechanism to the datasets. The approach is finally exemplified with a case study simulation.

Assessing VGI Data Quality

“…The quality of VGI will continue to be one of the most important barriers to the integration of VGI to authoritative data, and developing generic and flexible solutions such as the system proposed by Bordogna et al (2015) represents one tangible step forward; thus, we envisage that workflow developments will be a key area of research in the future. Standards agencies also need to recognise that there are new sources of spatial data and that existing standards must be adapted to include these sources or new standards must be developed.…”

“…However, some papers have appeared in which quality assurance workflows have been proposed. For example, Bordogna et al (2015) propose a flexible system that allows users to specify minimum acceptable quality levels based on their requirements (Figure 3). The system contains a series of quality indicators, including both standard …”

“…3: Scheme of the system proposed by Bordogna et al (2015) that allows users to specify minimum acceptable quality levels based on their requirements. internal quality measures such as positional accuracy and ones specifically geared towards VGI (see Section 2.2).…”

Sources of VGI for Mapping

“…For this reason a considerable quantity of literature has appeared on this topic (see e.g. Antoniou and Skopeliti, 2015;Bordogna et al, 2015;Flanagin and Metzger, 2008;Jokar Arsanjani et al, 2015a). There is an ISO standard for spatial quality that can be applied to VGI, but additional quality indicators are required due to the characteristics that are specific to VGI.…”

The Relevance of Protocols for VGI Collection

“…It is possible to impose a set of protocols in active VGI, but this is usually not possible when using passive VGI or CGI, where the data volumes are often larger than in active sources and hence the data need to be filtered if they are to be used. For example, Bordogna et al (2015) demonstrated how input data can be filtered based on minimum quality criteria specified by the user, for example to remove geotagged photographs downloaded from repositories such as Flickr and Panoramio. Hence this chapter limits its focus to active VGI projects, where the role played by protocols can be crucial for the quality of the data collected.…”